计算机“端口”是英文port的义译，可以认为是计算机与外界通讯交流的出口。

其中硬件领域的端口又称接口，如：USB端口、串行端口等。

软件领域的端口一般指网络中面向连接服务和无连接服务的通信协议端口，是一种抽象的软件结构，包括一些数据结构和I/O（基本输入输出）缓冲区。

可以先了解面向连接和无连接协议（Connection－Oriented and Connectionless Protocols）面向连接服务的主要特点有：面向连接服务要经过三个阶段：数据传数前，先建立连接，连接建立后再传输数据，数据传送完后，释放连接。

面向连接服务，可确保数据传送的次序和传输的可靠性。

无连接服务的特点是：无连接服务只有传输数据阶段。

消除了除数据通信外的其它开销。

只要发送实体是活跃的，无须接收实体也是活跃的。

它的优点是灵活方便、迅速，特别适合于传送少量零星的报文，但无连接服务不能防止报文的丢失、重复或失序。

区分“面向连接服务”和“无连接服务”的概念，特别简单、形象的例子是：打电话和写信。

两个人如果要通电话，必须先建立连接——拨号，等待应答后才能相互传递信息，最后还要释放连接——挂电话。

写信就没有那么复杂了，地址姓名填好以后直接往邮筒一扔，收信人就能收到。

TCP/IP协议在网络层是无连接的（数据包只管往网上发，如何传输和到达以及是否到达由网络设备来管理）。

而“端口”，是传输层的内容，是面向连接的。

协议里面低于1024的端口都有确切的定义，它们对应着因特网上常见的一些服务。

这些常见的服务可以划分为使用TCP端口（面向连接如打电话）和使用UDP端口（无连接如写信）两种。

网络中可以被命名和寻址的通信端口是操作系统的一种可分配资源。

由网络OSI（开放系统互联参考模型，Open System Interconnection Reference Model）七层协议可知，传输层与网络层最大的区别是传输层提供进程通信能力，网络通信的最终地址不仅包括主机地址，还包括可描述进程的某种标识。

所以TCP/IP 协议提出的协议端口，可以认为是网络通信进程的一种标识符。

应用程序（调入内存运行后一般称为：进程）通过系统调用与某端口建立连接（binding，绑定）后，传输层传给该端口的数据都被相应的进程所接收，相应进程发给传输层的数据都从该端口输出。

在TCP/IP 协议的实现中，端口操作类似于一般的I/O操作，进程获取一个端口，相当于获取本地唯一的I/O文件，可以用一般的读写方式访问。

类似于文件描述符，每个端口都拥有一个叫端口号的整数描述符，用来区别不同的端口。

由于TCP/IP 传输层的TCP和UDP两个协议是两个完全独立的软件模块，因此各自的端口号也相互独立。

如TCP有一个255号端口，UDP也可以有一个255号端口，两者并不冲突。

端口号有两种基本分配方式：第一种叫全局分配这是一种集中分配方式，由一个公认权威的中央机构根据用户需要进行统一分配，并将结果公布于众，第二种是本地分配，又称动态连接，即进程需要访问传输层服务时，向本地操作系统提出申请，操作系统返回本地唯一的端口号，进程再通过合适的系统调用，将自己和该端口连接起来（binding，绑定）。

TCP/IP端口号的分配综合了以上两种方式，将端口号分为两部分，少量的作为保留端口，以全局方式分配给服务进程。

每一个标准服务器都拥有一个全局公认的端口叫周知口，即使在不同的机器上，其端口号也相同。

剩余的为自由端口，以本地方式进行分配。

TCP和UDP 规定，小于256的端口才能作为保留端口。

按端口号可分为3大类：（1）公认端口（Well Known Ports）：从0到1023，它们紧密绑定（binding）于一些服务。

通常这些端口的通讯明确表明了某种服务的协议。

例如：80端口实际上总是HTTP通讯。

（2）注册端口（Registered Ports）：从1024到49151。

它们松散地绑定于一些服务。

也就是说有许多服务绑定于这些端口，这些端口同样用于许多其它目的。

例如：许多系统处理动态端口从1024左右开始。

（3）动态和/或私有端口（Dynamic and/or Private Ports）：从49152到65535。

理论上，不应为服务分配这些端口。

实际上，机器通常从1024起分配动态端口。

但也有例外：SUN的RPC端口从32768开始。

系统管理员可以“重定向”端口：一种常见的技术是把一个端口重定向到另一个地址。

例如默认的HTTP端口是80，不少人将它重定向到另一个端口，如8080。

如果是这样改了，要访问本文就应改用这个地址:8080/net/port.htm （当然，这仅仅是理论上的举例）。

实现重定向是为了隐藏公认的默认端口，降低受破坏率。

这样如果有人要对一个公认的默认端口进行攻击则必须先进行端口扫描。

大多数端口重定向与原端口有相似之处，例如多数HTTP端口由80变化而来：81，88，8000，8080，8888。

同样POP的端口原来在110，也常被重定向到1100。

也有不少情况是选取统计上有特别意义的数，象1234，23456，34567等。

许多人有其它原因选择奇怪的数，42，69，666，31337。

近来，越来越多的远程控制木马( Remote Access Trojans, RATs )采用相同的默认端口。

如NetBus的默认端口是12345。

Blake R. Swopes指出使用重定向端口还有一个原因，在UNIX系统上，如果你想侦听1024以下的端口需要有root权限。

如果你没有root权限而又想开web服务，你就需要将其安装在较高的端口。

此外，一些ISP的防火墙将阻挡低端口的通讯，这样的话即使你拥有整个机器你还是得重定向端口。

端口? ?? ?? ?? ?? ?功能英文注解? ?? ?? ?? ?? ?? ?功能中文注解1 tcpmux TCP Port Service Multiplexer 传输控制协议端口服务多路开关选择器2 compressnet Management Utility compressnet 管理实用程序3 compressnet Compression Process 压缩进程5 rje Remote Job Entry 远程作业登录7 echo Echo 回显9 discard Discard 丢弃11 systat Active Users 在线用户13 daytime Daytime 时间17 qotd Quote of the Day 每日引用18 msp Message Send Protocol 消息发送协议19 chargen Character Generator 字符发生器20 ftp-data File Transfer[Default Data] 文件传输协议(默认数据口)21 ftp File Transfer[Control] 文件传输协议(控制)22 ssh SSH Remote Login Protocol SSH远程登录协议23 telnet Telnet 终端仿真协议24 ? any private mail system 预留给个人用邮件系统25 smtp Simple Mail Transfer 简单邮件发送协议27 nsw-fe NSW User System FE NSW 用户系统现场工程师29 msg-icp MSG ICP MSG ICP31 msg-auth MSG Authentication MSG验证33 dsp Display Support Protocol 显示支持协议35 ? any private printer server 预留给个人打印机服务37 time Time 时间38 rap Route Access Protocol 路由访问协议39 rlp Resource Location Protocol 资源定位协议41 graphics Graphics 图形42 nameserver WINS Host Name Server WINS 主机名服务43 nicname Who Is "绰号" who is服务44 mpm-flags MPM FLAGS Protocol MPM(消息处理模块)标志协议45 mpm Message Processing Module [recv] 消息处理模块46 mpm-snd MPM [default send] 消息处理模块(默认发送口)47 ni-ftp NI FTP NI FTP48 auditd Digital Audit Daemon 数码音频后台服务49 tacacs Login Host Protocol (TACACS) TACACS登录主机协议50 re-mail-ck Remote Mail Checking Protocol 远程邮件检查协议51 la-maint IMP Logical Address Maintenance IMP(接口信息处理机)逻辑地址维护52 xns-time XNS Time Protocol 施乐网络服务系统时间协议53 domain Domain Name Server 域名服务器54 xns-ch XNS Clearinghouse 施乐网络服务系统票据交换55 isi-gl ISI Graphics Language ISI图形语言56 xns-auth XNS Authentication 施乐网络服务系统验证57 ? any private terminal access 预留个人用终端访问58 xns-mail XNS Mail 施乐网络服务系统邮件59 ? any private file service 预留个人文件服务60 ? Unassigned 未定义61 ni-mail NI MAIL NI邮件?62 acas ACA Services 异步通讯适配器服务63 whois+ whois+ WHOIS+64 covia Communications Integrator (CI) 通讯接口65 tacacs-ds TACACS-Database Service TACACS数据库服务66 sql*net Oracle SQL*NET Oracle SQL*NET67 bootps Bootstrap Protocol Server 引导程序协议服务端68 bootpc Bootstrap Protocol Client 引导程序协议客户端69 tftp Trivial File Transfer 小型文件传输协议70 gopher Gopher 信息检索协议71 netrjs-1 Remote Job Service 远程作业服务72 netrjs-2 Remote Job Service 远程作业服务73 netrjs-3 Remote Job Service 远程作业服务74 netrjs-4 Remote Job Service 远程作业服务75 ? any private dial out service 预留给个人拨出服务76 deos Distributed External Object Store 分布式外部对象存储77 ? any private RJE service 预留给个人远程作业输入服务78 vettcp vettcp 修正TCP?79 finger Finger 查询远程主机在线用户等信息80 http World Wide Web HTTP 全球信息网超文本传输协议81 hosts2-ns HOSTS2 Name Server HOST2名称服务82 xfer XFER Utility 传输实用程序83 mit-ml-dev MIT ML Device 模块化智能终端ML设备84 ctf Common Trace Facility 公用追踪设备85 mit-ml-dev MIT ML Device 模块化智能终端ML设备86 mfcobol Micro Focus Cobol Micro Focus Cobol编程语言87 ? any private terminal link 预留给个人终端连接88 kerberos Kerberos Kerberros安全认证系统89 su-mit-tg SU/MIT Telnet Gateway SU/MIT终端仿真网关90 dnsix DNSIX Securit Attribute Token Map DNSIX 安全属性标记图91 mit-dov MIT Dover Spooler MIT Dover假脱机92 npp Network Printing Protocol 网络打印协议93 dcp Device Control Protocol 设备控制协议94 objcall Tivoli Object Dispatcher Tivoli对象调度95 supdup SUPDUP96 dixie DIXIE Protocol Specification DIXIE协议规范97 swift-rvf（Swift Remote Virtural File Protocol）快速远程虚拟文件协议98 tacnews TAC News TAC新闻协议99 metagram Metagram Relay100 newacct [unauthorized use]reserved 0/tcp Reserved [JBP]reserved 0/udp Reserved [JBP]tcpmux 1/tcp TCP Port Service Multiplexer [MKL]tcpmux 1/udp TCP Port Service Multiplexer [MKL]compressnet 2/tcp Management Utility [BV15]compressnet 2/udp Management Utility [BV15]compressnet 3/tcp Compression Process [BV15]compressnet 3/udp Compression Process [BV15]rje 5/tcp Remote Job Entry [12,JBP]rje 5/udp Remote Job Entry [12,JBP]echo 7/tcp Echo [95,JBP]echo 7/udp Echo [95,JBP]discard 9/tcp Discard [94,JBP]discard 9/udp Discard [94,JBP]systat 11/tcp Active Users [89,JBP]systat 11/udp Active Users [89,JBP]daytime 13/tcp Daytime [93,JBP]daytime 13/udp Daytime [93,JBP]netstat 15/tcp Netstatqotd 17/tcp Quote of the Day [100,JBP]qotd 17/udp Quote of the Day [100,JBP]msp 18/tcp Message Send Protocol [RXN]msp 18/udp Message Send Protocol [RXN]chargen 19/tcp ttytst source Character Generatorchargen 19/udp ttytst source Character Generatorftp-data 20/tcp File Transfer [Default Data] [96,JBP] ftp-data 20/udp File Transfer [Default Data] [96,JBP] ftp 21/tcp File Transfer [Control] [96,JBP]ftp 21/udp File Transfer [Control] [96,JBP]ssh 22/tcp Secure Shell - RSA encrypted rshtelnet 23/tcp Telnet [112,JBP]telnet 23/udp Telnet [112,JBP]priv-mail 24/tcp any private mail system [RA11]priv-mail 24/udp any private mail system [RA11]smtp 25/tcp Simple Mail Transfer [102,JBP]smtp 25/udp Simple Mail Transfer [102,JBP]nsw-fe 27/tcp NSW User System FE [24,RHT]nsw-fe 27/udp NSW User System FE [24,RHT]msg-icp 29/tcp MSG ICP [85,RHT]msg-icp 29/udp MSG ICP [85,RHT]msg-auth 31/tcp MSG Authentication [85,RHT]msg-auth 31/udp MSG Authentication [85,RHT]dsp 33/tcp Display Support Protocol [EXC]dsp 33/udp Display Support Protocol [EXC]priv-print 35/tcp any private printer server [JBP] priv-print 35/udp any private printer server [JBP] time 37/tcp Time [108,JBP]time 37/udp Time [108,JBP]rap 38/tcp Route Access Protocolrap 38/udp Route Access Protocolrlp 39/tcp resource Resource Location Protocolrlp 39/udp resource Resource Location Protocol graphics 41/tcp Graphics [129,JBP]graphics 41/udp Graphics [129,JBP]nameserver 42/tcp Host Name Server [99,JBP] nameserver 42/udp Host Name Server [99,JBP]nicname 43/tcp Who Is [55,ANM2]nicname 43/udp Who Is [55,ANM2]mpm-flags 44/tcp MPM FLAGS Protocol [JBP]mpm-flags 44/udp MPM FLAGS Protocol [JBP]mpm 45/tcp Message Processing Module [recv] [98,JBP] mpm 45/udp Message Processing Module [recv] [98,JBP] mpm-snd 46/tcp MPM [default send] [98,JBP]mpm-snd 46/udp MPM [default send] [98,JBP]ni-ftp 47/tcp NI FTP [134,SK8]ni-ftp 47/udp NI FTP [134,SK8]auditd 48/tcp Digital Audit Daemonauditd 48/udp Digital Audit Daemonlogin 49/tcp Login Host Protocol [PHD1]login 49/udp Login Host Protocol [PHD1]re-mail-ck 50/tcp Remote Mail Checking Protocol [171,SXD1] re-mail-ck 50/udp Remote Mail Checking Protocol [171,SXD1] la-maint 51/tcp IMP Logical Address Maintenance [76,AGM] la-maint 51/udp IMP Logical Address Maintenance [76,AGM] xns-time 52/tcp XNS Time Protocol [SXA]xns-time 52/udp XNS Time Protocol [SXA]domain 53/tcp Domain Name Server [81,95,PM1]domain 53/udp Domain Name Server [81,95,PM1]xns-ch 54/tcp XNS Clearinghouse [SXA]xns-ch 54/udp XNS Clearinghouse [SXA]isi-gl 55/tcp ISI Graphics Language [7,RB9]isi-gl 55/udp ISI Graphics Language [7,RB9]xns-auth 56/tcp XNS Authentication [SXA]xns-auth 56/udp XNS Authentication [SXA]mtp 57/tcp deprecatedpriv-term 57/tcp any private terminal access [JBP]priv-term 57/udp any private terminal access [JBP]xns-mail 58/tcp XNS Mail [SXA]xns-mail 58/udp XNS Mail [SXA]priv-file 59/tcp any private file service [JBP]priv-file 59/udp any private file service [JBP]ni-mail 61/tcp NI MAIL [5,SK8]ni-mail 61/udp NI MAIL [5,SK8]acas 62/tcp ACA Services [EXW]acas 62/udp ACA Services [EXW]via-ftp 63/tcp VIA Systems - FTP [DXD]via-ftp 63/udp VIA Systems - FTP [DXD]whois++ 63/tcpwhois++ 63/udpcovia 64/tcp Communications Integrator (CI) [TXD]covia 64/udp Communications Integrator (CI) [TXD]tacacs-ds 65/tcp TACACS-Database Service [3,KH43]tacacs-ds 65/udp TACACS-Database Service [3,KH43]sql*net 66/tcp Oracle SQL*NET [JFH2]sql*net 66/udp Oracle SQL*NET [JFH2]bootps 67/tcp Bootstrap Protocol Server [36,WJC2]bootps 67/udp Bootstrap Protocol Server [36,WJC2]bootpc 68/tcp Bootstrap Protocol Client [36,WJC2]bootpc 68/udp Bootstrap Protocol Client [36,WJC2] tftp 69/tcp Trivial File Transfer [126,DDC1]tftp 69/udp Trivial File Transfer [126,DDC1] gopher 70/tcp Gopher [MXC1]gopher 70/udp Gopher [MXC1]netrjs-1 71/tcp Remote Job Service [10,RTB3]netrjs-1 71/udp Remote Job Service [10,RTB3]netrjs-2 72/tcp Remote Job Service [10,RTB3]netrjs-2 72/udp Remote Job Service [10,RTB3]netrjs-3 73/tcp Remote Job Service [10,RTB3]netrjs-3 73/udp Remote Job Service [10,RTB3]netrjs-4 74/tcp Remote Job Service [10,RTB3]netrjs-4 74/udp Remote Job Service [10,RTB3]priv-dial 75/tcp any private dial out service [JBP] priv-dial 75/udp any private dial out service [JBP] deos 76/tcp Distributed External Object Store deos 76/udp Distributed External Object Store netrjs 77/tcppriv-rje 77/tcp any private RJE service [JBP]priv-rje 77/udp any private RJE service [JBP] vettcp 78/tcp vettcp [CXL1]vettcp 78/udp vettcp [CXL1]finger 79/tcp Finger [52,KLH]finger 79/udp Finger [52,KLH]http 80/tcp www www-http World Wide Web HTTPhttp 80/udp www www-http World Wide Web HTTPwww 80/tcp World Wide Web HTTP [TXL]www 80/udp World Wide Web HTTP [TXL]hosts2-ns 81/tcp HOSTS2 Name Server [EAK1]hosts2-ns 81/udp HOSTS2 Name Server [EAK1]xfer 82/tcp XFER Utility [TXS2]xfer 82/udp XFER Utility [TXS2]mit-ml-dev 83/tcp MIT ML Device [DXR3]mit-ml-dev 83/udp MIT ML Device [DXR3]ctf 84/tcp Common Trace Facility [HXT]ctf 84/udp Common Trace Facility [HXT]mit-ml-dev 85/tcp MIT ML Device [DXR3]mit-ml-dev 85/udp MIT ML Device [DXR3]mfcobol 86/tcp Micro Focus Cobol [SXE]mfcobol 86/udp Micro Focus Cobol [SXE]priv-term-l 87/tcp any private terminal link [JBP] priv-term-l 87/udp any private terminal link [JBP]ttylink 87/tcpkerberos 88/tcp Kerberos [BCN]kerberos 88/udp Kerberos [BCN]su-mit-tg 89/tcp SU/MIT Telnet Gateway [MRC]su-mit-tg 89/udp SU/MIT Telnet Gateway [MRC]dnsix 90/tcp DNSIX Securit Attribute Token Map [CXW1] dnsix 90/udp DNSIX Securit Attribute Token Map [CXW1]mit-dov 91/tcp MIT Dover Spooler [EBM]mit-dov 91/udp MIT Dover Spooler [EBM]npp 92/tcp Network Printing Protocol [LXM]npp 92/udp Network Printing Protocol [LXM]dcp 93/tcp Device Control Protocol [DT15]dcp 93/udp Device Control Protocol [DT15]objcall 94/tcp Tivoli Object Dispatcher [TXB1]objcall 94/udp Tivoli Object Dispatcher [TXB1]supdup 95/tcp SUPDUP [27,MRC]supdup 95/udp SUPDUP [27,MRC]dixie 96/tcp DIXIE Protocol Specification [TXH1]dixie 96/udp DIXIE Protocol Specification [TXH1]swift-rvf 97/tcp Swift Remote Vitural File Protocol [MXR] swift-rvf 97/udp Swift Remote Vitural File Protocol [MXR] tacnews 98/tcp TAC News [ANM2]tacnews 98/udp TAC News [ANM2]metagram 99/tcp Metagram Relay [GEOF]metagram 99/udp Metagram Relay [GEOF]newacct 100/tcp [unauthorized use]hostname 101/tcp hostnames NIC Host Name Serverhostname 101/udp hostnames NIC Host Name Serveriso-tsap 102/tcp tsap ISO-TSAP Class 0iso-tsap 102/udp tsap ISO-TSAP Class 0gppitnp 103/tcp Genesis Point-to-Point Trans Net [PXM1] gppitnp 103/udp Genesis Point-to-Point Trans Net [PXM1] x400 103/tcp ISO Mailacr-nema 104/tcp ACR-NEMA Digital Imag. & Comm. 300 [PXM1] acr-nema 104/udp ACR-NEMA Digital Imag. & Comm. 300 [PXM1] x400-snd 104/tcp ISO Mailcsnet-ns 105/tcp Mailbox Name Nameserver [127,MS56]csnet-ns 105/udp Mailbox Name Nameserver [127,MS56]3com-tsmux 106/tcp 3COM-TSMUX [JXS5]3com-tsmux 106/udp 3COM-TSMUX [JXS5]rtelnet 107/tcp Remote Telnet Service [101,JBP]rtelnet 107/udp Remote Telnet Service [101,JBP]snagas 108/tcp SNA Gateway Access Server [KXM]snagas 108/udp SNA Gateway Access Server [KXM]pop2 109/tcp postoffice Post Office Protocol - Version 2 pop2 109/udp postoffice Post Office Protocol - Version 2 pop3 110/tcp Post Office Protocol - Version 3 [122,MTR] pop3 110/udp Post Office Protocol - Version 3 [122,MTR] sunrpc 111/tcp rpcbind SUN Remote Procedure Callsunrpc 111/udp rpcbind SUN Remote Procedure Callmcidas 112/tcp McIDAS Data Transmission Protocol [GXD] mcidas 112/udp McIDAS Data Transmission Protocol [GXD] auth 113/tcp Authentication Service [130,MCSJ]auth 113/udp Authentication Service [130,MCSJ]audionews 114/tcp Audio News Multicast [MXF2]audionews 114/udp Audio News Multicast [MXF2]sftp 115/tcp Simple File Transfer Protocol [73,MKL1]sftp 115/udp Simple File Transfer Protocol [73,MKL1] ansanotify 116/tcp ANSA REX Notify [NXH]ansanotify 116/udp ANSA REX Notify [NXH]uucp-path 117/tcp UUCP Path Service [44,MAE]uucp-path 117/udp UUCP Path Service [44,MAE]sqlserv 118/tcp SQL Services [LXB3]sqlserv 118/udp SQL Services [LXB3]nntp 119/tcp Network News Transfer Protocol [65,PL4]nntp 119/udp Network News Transfer Protocol [65,PL4] cfdptkt 120/tcp CFDPTKT [JXO3]cfdptkt 120/udp CFDPTKT [JXO3]erpc 121/tcp Encore Expedited Remote Pro.Call [132,JXO] erpc 121/udp Encore Expedited Remote Pro.Call [132,JXO] smakynet 122/tcp SMAKYNET [MXO]smakynet 122/udp SMAKYNET [MXO]ntp 123/tcp Network Time Protocol [80,DLM1]ntp 123/udp Network Time Protocol [80,DLM1]ansatrader 124/tcp ANSA REX Trader [NXH]ansatrader 124/udp ANSA REX Trader [NXH]locus-map 125/tcp Locus PC-Interface Net Map Ser [137,EP53] locus-map 125/udp Locus PC-Interface Net Map Ser [137,EP53] unitary 126/tcp Unisys Unitary Login [FEIL]unitary 126/udp Unisys Unitary Login [FEIL]locus-con 127/tcp Locus PC-Interface Conn Server [137,EP53] locus-con 127/udp Locus PC-Interface Conn Server [137,EP53] gss-xlicen 128/tcp GSS X License Verification [JXL]gss-xlicen 128/udp GSS X License Verification [JXL]pwdgen 129/tcp Password Generator Protocol [141,FJW] pwdgen 129/udp Password Generator Protocol [141,FJW] cisco-fna 130/tcp cisco FNATIVE [WXB]cisco-fna 130/udp cisco FNATIVE [WXB]cisco-tna 131/tcp cisco TNATIVE [WXB]cisco-tna 131/udp cisco TNATIVE [WXB]cisco-sys 132/tcp cisco SYSMAINT [WXB]cisco-sys 132/udp cisco SYSMAINT [WXB]statsrv 133/tcp Statistics Service [DLM1]statsrv 133/udp Statistics Service [DLM1]ingres-net 134/tcp INGRES-NET Service [MXB]ingres-net 134/udp INGRES-NET Service [MXB]loc-srv 135/tcp Location Service [JXP]loc-srv 135/udp Location Service [JXP]profile 136/tcp PROFILE Naming System [LLP]profile 136/udp PROFILE Naming System [LLP]netbios-ns 137/tcp NETBIOS Name Service [JBP]netbios-ns 137/udp NETBIOS Name Service [JBP]netbios-dgm 138/tcp NETBIOS Datagram Service [JBP] netbios-dgm 138/udp NETBIOS Datagram Service [JBP] netbios-ssn 139/tcp NETBIOS Session Service [JBP] netbios-ssn 139/udp NETBIOS Session Service [JBP] emfis-data 140/tcp EMFIS Data Service [GB7]emfis-data 140/udp EMFIS Data Service [GB7]emfis-cntl 141/tcp EMFIS Control Service [GB7]emfis-cntl 141/udp EMFIS Control Service [GB7]bl-idm 142/tcp Britton-Lee IDM [SXS1]bl-idm 142/udp Britton-Lee IDM [SXS1]imap2 143/tcp Interim Mail Access Protocol v2 [MRC] imap2 143/udp Interim Mail Access Protocol v2 [MRC] NeWS 144/tcp Window SystemNeWS 144/udp Window Systemnews 144/tcp NewS window system [JAG]news 144/udp NewS window system [JAG]uaac 145/tcp UAAC Protocol [DAG4]uaac 145/udp UAAC Protocol [DAG4]iso-tp0 146/tcp ISO-IP0 [86,MTR]iso-tp0 146/udp ISO-IP0 [86,MTR]iso-ip 147/tcp ISO-IP [MTR]iso-ip 147/udp ISO-IP [MTR]cronus 148/tcp CRONUS-SUPPORT [135,JXB]cronus 148/udp CRONUS-SUPPORT [135,JXB]aed-512 149/tcp AED 512 Emulation Service [AXB]aed-512 149/udp AED 512 Emulation Service [AXB]sql-net 150/tcp SQL-NET [MXP]sql-net 150/udp SQL-NET [MXP]hems 151/tcp HEMS [87,CXT]hems 151/udp HEMS [87,CXT]bftp 152/tcp Background File Transfer Program [AD14]bftp 152/udp Background File Transfer Program [AD14]sgmp 153/tcp SGMP [37,MS9]sgmp 153/udp SGMP [37,MS9]netsc-prod 154/tcp NETSC [SH37]netsc-prod 154/udp NETSC [SH37]netsc-dev 155/tcp NETSC [SH37]netsc-dev 155/udp NETSC [SH37]sqlsrv 156/tcp SQL Service [CMR]sqlsrv 156/udp SQL Service [CMR]knet-cmp 157/tcp KNET/VM Command/Message Protocol[77,GSM11] knet-cmp 157/udp KNET/VM Command/Message Protocol[77,GSM11] pcmail-srv 158/tcp PCMail Server [19,MXL]pcmail-srv 158/udp PCMail Server [19,MXL]nss-routing 159/tcp NSS-Routing [JXR]nss-routing 159/udp NSS-Routing [JXR]sgmp-traps 160/tcp SGMP-TRAPS [37,MS9]sgmp-traps 160/udp SGMP-TRAPS [37,MS9]snmp 161/tcp SNMP [15,MTR]snmp 161/udp SNMP [15,MTR]snmptrap 162/tcp SNMPTRAP [15,MTR]snmptrap 162/udp SNMPTRAP [15,MTR]cmip-man 163/tcp CMIP/TCP Manager [4,AXB1]cmip-man 163/udp CMIP/TCP Manager [4,AXB1]cmip-agent 164/tcp CMIP/TCP Agentsmip-agent 164/udp CMIP/TCP Agentxns-courier 165/tcp Xerox 144,SXA]xns-courier 165/udp Xerox [144,SXA]s-net 166/tcp Sirius Systems [BXL]s-net 166/udp Sirius Systems [BXL]namp 167/tcp NAMP [MS9]namp 167/udp NAMP [MS9]rsvd 168/tcp RSVD [NT12]rsvd 168/udp RSVD [NT12]send 169/tcp SEND [WDW11]send 169/udp SEND [WDW11]print-srv 170/tcp Network PostScript [BKR]print-srv 170/udp Network PostScript [BKR]multiplex 171/tcp Network Innovations Multiplex [KXD] multiplex 171/udp Network Innovations Multiplex [KXD]cl/1 172/tcp Network Innovations CL/1 [KXD]cl/1 172/udp Network Innovations CL/1 [KXD]xyplex-mux 173/tcp Xyplex [BXS]xyplex-mux 173/udp Xyplex [BXS]mailq 174/tcp MAILQ [RXZ]mailq 174/udp MAILQ [RXZ]vmnet 175/tcp VMNET [CXT]vmnet 175/udp VMNET [CXT]genrad-mux 176/tcp GENRAD-MUX [RXT]genrad-mux 176/udp GENRAD-MUX [RXT]xdmcp 177/tcp X Display Manager Control Protocol [RWS4] xdmcp 177/udp X Display Manager Control Protocol [RWS4] NextStep 178/udp nextstep NeXTStep NextStep Window Server nextstep 178/tcp NextStep NeXTStep NextStep Window Server bgp 179/tcp Border Gateway Protocol [KSL]bgp 179/udp Border Gateway Protocol [KSL]ris 180/tcp Intergraph [DXB]ris 180/udp Intergraph [DXB]unify 181/tcp Unify [VXS]unify 181/udp Unify [VXS]audit 182/tcp Unisys Audit SITP [GXG]audit 182/udp Unisys Audit SITP [GXG]ocbinder 183/tcp OCBinder [JXO1]ocbinder 183/udp OCBinder [JXO1]ocserver 184/tcp OCServer [JXO1]ocserver 184/udp OCServer [JXO1]remote-kis 185/tcp Remote-KIS [RXD1]remote-kis 185/udp Remote-KIS [RXD1]kis 186/tcp KIS Protocol [RXD1]kis 186/udp KIS Protocol [RXD1]aci 187/tcp Application Communication Interface [RXC1] aci 187/udp Application Communication Interface [RXC1] mumps 188/tcp Plus Five''s MUMPS [HS23]mumps 188/udp Plus Five''s MUMPS [HS23]qft 189/tcp Queued File Transport [WXS]qft 189/udp Queued File Transport [WXS]cacp 190/udp Gateway Access Control Protocolgacp 190/tcp Gateway Access Control Protocolprospero 191/tcp Prospero Directory Serviceprospero 191/udp Prospero Directory Serviceosu-nms 192/tcp OSU Network Monitoring System [DXK]osu-nms 192/udp OSU Network Monitoring System [DXK]srmp 193/tcp Spider Remote Monitoring Protocol [TXS]srmp 193/udp Spider Remote Monitoring Protocol [TXS]irc 194/tcp Internet Relay Chat Protocol [JXO2]irc 194/udp Internet Relay Chat Protocol [JXO2]dn6-nlm-aud 195/tcp DNSIX Network Level Module Audit [LL69]dn6-nlm-aud 195/udp DNSIX Network Level Module Audit [LL69]dn6-smm-red 196/tcp DNSIX Session Mgt Module Audit Redir[LL69] dn6-smm-red 196/udp DNSIX Session Mgt Module Audit Redir[LL69] dls 197/tcp Directory Location Service [SXB]dls 197/udp Directory Location Service [SXB]dls-mon 198/tcp Directory Location Service Monitor [SXB]dls-mon 198/udp Directory Location Service Monitor [SXB] smux 199/tcp SMUX [MTR]smux 199/udp SMUX [MTR]src 200/tcp IBM System Resource Controller [GXM]src 200/udp IBM System Resource Controller [GXM]at-rtmp 201/tcp AppleTalk Routing Maintenance [RXC]at-rtmp 201/udp AppleTalk Routing Maintenance [RXC]at-nbp 202/tcp AppleTalk Name Binding [RXC]at-nbp 202/udp AppleTalk Name Binding [RXC]at-3 203/tcp AppleTalk Unused [RXC]at-3 203/udp AppleTalk Unused [RXC]at-echo 204/tcp AppleTalk Echo [RXC]at-echo 204/udp AppleTalk Echo [RXC]at-5 205/tcp AppleTalk Unused [RXC]at-5 205/udp AppleTalk Unused [RXC]at-zis 206/tcp AppleTalk Zone Information [RXC]at-zis 206/udp AppleTalk Zone Information [RXC]at-7 207/tcp AppleTalk Unused [RXC]at-7 207/udp AppleTalk Unused [RXC]at-8 208/tcp AppleTalk Unused [RXC]at-8 208/udp AppleTalk Unused [RXC]tam 209/tcp Trivial Authenticated Mail Protocol [DXB1]tam 209/udp Trivial Authenticated Mail Protocol [DXB1]z39.50 210/tcp ANSI Z39.50 [MXN]z39.50 210/udp ANSI Z39.50 [MXN]914c/g 211/tcp Texas Instruments 914C/G Terminal [BXH1]914c/g 211/udp Texas Instruments 914C/G Terminal [BXH1]anet 212/tcp ATEXSSTR [JXT]anet 212/udp ATEXSSTR [JXT]ipx 213/tcp IPX [DP666]ipx 213/udp IPX [DP666]vmpwscs 214/tcp VM PWSCS [DXS]vmpwscs 214/udp VM PWSCS [DXS]softpc 215/tcp Insignia Solutions [MXT]softpc 215/udp Insignia Solutions [MXT]atls 216/tcp Access Technology License Server [LXD]atls 216/udp Access Technology License Server [LXD] dbase 217/tcp dBASE Unix [DXG1]dbase 217/udp dBASE Unix [DXG1]mpp 218/tcp Netix Message Posting Protocol [STY]mpp 218/udp Netix Message Posting Protocol [STY]uarps 219/tcp Unisys ARPs [AXM1]uarps 219/udp Unisys ARPs [AXM1]imap3 220/tcp Interactive Mail Access Protocol v3 [JXR2] imap3 220/udp Interactive Mail Access Protocol v3 [JXR2] fln-spx 221/tcp Berkeley rlogind with SPX auth [KXA]fln-spx 221/udp Berkeley rlogind with SPX auth [KXA]fsh-spx 222/tcp Berkeley rshd with SPX auth [KXA]fsh-spx 222/udp Berkeley rshd with SPX auth [KXA]rsh-spx 222/tcp Berkeley rshd with SPX authrsh-spx 222/udp Berkeley rshd with SPX authcdc 223/tcp Certificate Distribution Center [KXA]cdc 223/udp Certificate Distribution Center [KXA]sur-meas 243/tcp Survey Measurement [6,DDC1]sur-meas 243/udp Survey Measurement [6,DDC1]link 245/tcp LINK [1,RDB2]link 245/udp LINK [1,RDB2]dsp3270 246/tcp Display Systems Protocol [39,WJS1]dsp3270 246/udp Display Systems Protocol [39,WJS1]pdap 344/tcp Prospero Data Access Protocolpdap 344/udp Prospero Data Access Protocolpawserv 345/tcp Perf Analysis Workbenchpawserv 345/udp Perf Analysis Workbenchzserv 346/tcp Zebra serverzserv 346/udp Zebra serverfatserv 347/tcp Fatmen Serverfatserv 347/udp Fatmen Servercsi-sgwp 348/tcp Cabletron Management Protocolcsi-sgwp 348/udp Cabletron Management Protocolclearcase 371/tcp Clearcase [DXL1]clearcase 371/udp Clearcase [DXL1]ulistserv 372/tcp Unix Listserv [AXK]ulistserv 372/udp Unix Listserv [AXK]legent-1 373/tcp Legent Corporation [KXB]legent-1 373/udp Legent Corporation [KXB]legent-2 374/tcp Legent Corporation [KXB]legent-2 374/udp Legent Corporation [KXB]hassle 375/tcphassle 375/udpnip 376/tcp Amiga Envoy Network Inquiry Protonip 376/udp Amiga Envoy Network Inquiry PrototnETOS 377/tcp NEC CorporationtnETOS 377/udp NEC CorporationdsETOS 378/tcp NEC CorporationdsETOS 378/udp NEC Corporationis99c 379/tcp TIA/EIA/IS-99 modem clientis99c 379/udp TIA/EIA/IS-99 modem clientis99s 380/tcp TIA/EIA/IS-99 modem serveris99s 380/udp TIA/EIA/IS-99 modem serverhp-collector 381/tcp hp performance data collectorhp-collector 381/udp hp performance data collectorhp-managed-node 382/tcp hp performance data managed nodehp-managed-node 382/udp hp performance data managed nodehp-alarm-mgr 383/tcp hp performance data alarm managerhp-alarm-mgr 383/udp hp performance data alarm managerarns 384/tcp A Remote Network Server Systemarns 384/udp A Remote Network Server Systemibm-app 385/tcp IBM Applicationasa 386/tcp ASA Message Router Object Def.asa 386/udp ASA Message Router Object Def.aurp 387/tcp Appletalk Update-Based Routing Pro.aurp 387/udp Appletalk Update-Based Routing Pro.unidata-ldm 388/tcp Unidata LDM Version 4unidata-ldm 388/udp Unidata LDM Version 4ldap 389/tcp Lightweight Directory Access Protocolldap 389/udp Lightweight Directory Access Protocolentrustclient 389/tcp Entrustclient - NorTel DES auth network see 709/tcp uis 390/tcpuis 390/udpsynotics-relay 391/tcp SynOptics SNMP Relay Portsynotics-relay 391/udp SynOptics SNMP Relay Portsynotics-broker 392/tcp SynOptics Port Broker Port synotics-broker 392/udp SynOptics Port Broker Port dis 393/tcp Data Interpretation Systemdis 393/udp Data Interpretation Systemembl-ndt 394/tcp EMBL Nucleic Data Transferembl-ndt 394/udp EMBL Nucleic Data Transfernetcp 395/tcp NETscout Control Protocolnetcp 395/udp NETscout Control Protocolnetware-ip 396/tcp Novell Netware over IPnetware-ip 396/udp Novell Netware over IPmptn 397/tcp Multi Protocol Trans. Net.mptn 397/udp Multi Protocol Trans. Net.kryptolan 398/tcpkryptolan 398/udpiso-tsap-c2 399/tcp ISO-TSAP Class 2iso-tsap-c2 399/udp ISO-TSAP Class 2work-sol 400/tcp Workstation Solutionswork-sol 400/udp Workstation Solutionsups 401/tcp Uninterruptible Power Supplyups 401/udp Uninterruptible Power Supplygenie 402/tcp Genie Protocolgenie 402/udp Genie Protocoldecap 403/tcpdecap 403/udpnced 404/tcpnced 404/udpncld 405/tcpncld 405/udpimsp 406/tcp Interactive Mail Support Protocol imsp 406/udp Interactive Mail Support Protocol timbuktu 407/tcptimbuktu 407/udpprm-sm 408/tcp Prospero Resource Manager Sys. Man. prm-sm 408/udp Prospero Resource Manager Sys. Man. prm-nm 409/tcp Prospero Resource Manager Node Man. prm-nm 409/udp Prospero Resource Manager Node Man. decladebug 410/tcp DECLadebug Remote Debug Protocol decladebug 410/udp DECLadebug Remote Debug Protocol rmt 411/tcp Remote MT Protocolrmt 411/udp Remote MT Protocolsynoptics-trap 412/tcp Trap Convention Port synoptics-trap 412/udp Trap Convention Port。